拾遗：不用使 sizeof 获取数组大小

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#include <stdio.h>
#include <unistd.h>

int
main(void) {
    int A[] = {};
    size_t num = (int *)(&A + ) - (int *)&A;
    size_t len = (char *)(&A + ) - (char *)&A;
    printf("数组元素个数是 %zd\n字节总长度是 %zd\n", num, len);
    return ;
}

[fh@dell Trash]$ ./a.out
数组元素个数是
字节总长度是 

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